Cord testing machine



Feb. 12, 1935. G. D. MALLORY CORD TESTING MACHINE Filed May 31, 1930 ,llll||| lllllllllllllllllll l lllllllll Ill l IIIJI ||`..\,||I||II..|. I. III |||||l|..|.,'||

----!------.T-`.. il- ,|...-,--|,M Il-- f e--- l-- -..i -i II I N, Si WQ N mw m n MMM/nv E .bm mm 99 m. www nl 4 w ...rI I \..3L Wl, NM \dm msg. HM N sf... E E

v dkowqs Patented Feb. 12, 1935 'UNITED STATES 3 1,99o,a95 3 com) TESTING MAcHmE Gerald D. Mallory, Akron, Ohio, assignor to Wingfoot Corporation, Akron, Ohio, a corporation of Delaware This invention relates to apparatus for testing flexible materials, and it has particular relation to a machine for testing the flexing durability of a plurality of cords.

The object of the invention is to provide a machine for simultaneously comparing the flexing durabilities of elongate pieces lof flexible material.

Particularly the invention is employed for comparing the flexing durability of cords such as those used in the manufacture of pneumatic tires. Such a comparison is desirable because it indicates the comparative resistances of .different cords to stresses set up in tires during their'operation over irregular surfaces. The invention comprises stationary clamps for securing adiacent ends of a plurality of cords, and movable clamps engaging the other ends of the cords for tensioning them. Prior to the application of tension to the cords, their intermediate portions are looped about a rod or roller. After the cords are tensioned, the rod or roller is reciprocated -rapidly along the cords, thereby subjecting the latter to considerable exion stresses. This movement of the rod or roller iscontinued until one or all of the cords fail.

For a better understanding ofthe invention, reference may now be had to the accompanying drawing, forming a part of this specification in which:

Fig. 1 is a plan view of a testing apparatus constructed according to the invention;

Fig. 2 is an elevational view of the construction shown by Fig. 1; f

Fig. 3 .is a cross-sectional view taken substantially along line III-III of Fig. 1; and

Fig. 4 is a cross-sectional view, on a large scale, taken substantially along line IV-IV of Fig. 1.

In practicing the invention, a base 10 is supported at each end by legs 1l. The upper surface of the base is provided with longitudinally disposed iianges 13 and 14, having in their adjacent surfaces, guides or grooves 16 and 17, commensurate in length to that of the flanges. A crosshead 20 is slidably mounted in the guides 16 and 17, and is formed on its upper surface with a pair Y of integral blocks 69 and 61 which support clamps '24 and 25 respectively. 'I'hese clamps are alike in construction, and it is apparent, therefore,

that the same reference numerals may be em-v head 67, is threaded into the opening 65, with its head 67 substantially spaced from the surface 63. A clamping member 68 having an opening 72-is mounted loosely upon the bolt 65, and is provided with an aperture which slidably receives the pin 64. Hence the clamping member -is pre.

vented from rotating but is free to move vertically, relative to the block. The aperture 72 is ,enlarged at its lower end,as indicated at 74, to. receive a helical spring 75 which normally abuts the surface 63 of the block and urges the clamping member upwardly.

The lower side of the clamping member 68 has a plain surface 77 which is adapted to cooperate in clamping relation with the, surface 63 of the block. One end 78 of the clamping member extends vertically, and is provided with a curved surface 79 which merges into the surface 77. 'I'he `surface 79 is bounded on its side, by small ribs whereby a cord, or the like, easily is Amaintained upon the surface. The upper side of the clamping member is provided with a horizontal surface 84, and laterally inclined surfaces 85 and 86, disposed on opposite sides of the surface 84.

A cam 89 is mounted rotatably upon the bolt 66, and the lower side thereof is formed with a. pair of diametrically disposed horizontal surfaces 92 which normally rest upon the horizontal surface 84 .of the clamping member. Between the surfaces 92, cam surfaces 95 and 96 also are diametrically disposed and have their lowest pointsV normally below the surfaces 92. I

It isapparent that when the cam is turned on the bolt 66, V4the cam surfaces 95 and 96 ride over the inclined surfaces 85 and 86 and force vthe clamping member 68 downwardly. Continued turning of the cam brings the lowermost lPA'luN OFFICE. 1

points of the cam surfaces into contacting relav tion with the horizontal surface 84, causing the clamping member to loe-locked in its lowermost position adjacent the base 61 of the cross-head. To facilitate turning of the cam, a handle 97 is secured thereto. The clamping member in its lowermost position is adapted to secure a cord, or thelike, between the surfaces 63 and 77. 'Ihe distance between the clamping member 68 and the block 61 may be varied by adjustment of the screw 66 whereby materials of different thicknesses may be clamped securely.

The.`crosshead 29 is moved in the guides 16 and 17, by a screw 36 threaded through a lug 27 on the cross-head, and non-slidably journaled in a bearing 33 at one end of the base 10. A handle 37 integral with the screwserves to facilitate its operation. 'Ihe other end of the base 10 is provided with clamps 30 and 31 which are construct-v will be apparent to those skilled in the art that ed in the same manner as the clamps 24 and 25. A more detailed description of the clamps, crosshead and means for moving the latter ,is described and shown in the application of Kochheiser et al., Serial No. 256,247.

A cord flexing device mounted upon the base 10 comprises supports 46 and 47 having portions 48 and 49 slidably disposed in the guides 16and 17 respectively. Should it be desired, anti-friction bearings may be provided between the portions 48 and 49 of the device 45, and the guides 16 and 17 to facilitate movement of the device. A roller 51 has its ends rotatably mounted in the upper ends of the supports 46 and 47, respec.

tively. A handle 52 having plates 53 and 54 secured thereto is pivoted on the roller 51 which extends through the plates.

In operating the apparatus described. two cords 59- and 58 are fastened between the clamps 24 and 30, and4 25 and 31, Y respectively, with the cross-head 20 in the position shown by broken lines in Fig. 2. The cords are then looped about the roller 51 of the exing device 45, carebeing taken to loop both cords in the same manner, after which the cords are elongated to the same extent by rotation oi the screw 36 until the crosshead assumes the position shown in Fig. 1. Then the roller 51 is reciprocated longitudinally of the cords, thus repeatedly flexing the cords until one of them fails, unless both cords should be ot the same durability. It is therefore apparent `that cords of unequal durabilities may be readily tested and their comparative ilexing durabilities demonstrated.

If it is desired, the iiexingdevice 45 can be employed without the use of the supports 46 and 47 which are slidably removable from the guides 16 and 17 by means of the open ends 101 and 102 of the guides 16 and 17 respectively. In such a construction, the cords are looped about the roller 51 and tensioned, and then the roller is manually reciprocated longitudinally oi' the cords.

From the foregoing description it is apparent that the apparatus disclosed is adapted-for demonstrating the qualities o! different kinds oi' cords,`

and particularly their` ilexing durabilities. The construction of the apparatus is such that it may easily be transported from place to place.

Although only the preferred form of the invention has been described and shown in detail, it

the invention is not so limited but that various minor modiiications may be made therein, without departing from the spirit oi' the invention or from the scope of the appended claims.

What I claim is: l

1. A testing machine comprising a base, an adinstable member mounted on the base, means for securing the ends oi pieces of materials4 to the hase and the adjustable member respectively, and a common means for simultaneously ilexing said materials, said common means comprising a pin ol' small diameter which may be moved longitudinally of the -materials and about which the materials are looped, and a handle attached to said pin.

2.Atestingniachlneco'rnprisingabase,anad-vv justable member mounted on the base, means ior securing the ends oi pieces ot materials to the base and the adjustable member respectively, and a common means tor simultaneously flexing said materials, said common means comprising a pin of small diameter about which the materials are looped, a handle attached to said-pin, and means whereby said pin is movable longitudinally of the materials.

3. A machine adapted to comparatively test the flexing durability oi' dissimilar cords comprising a base. means for maintaining the cords at the same elongation comprising an adjustable member molmted on the base, means for securing the ends oi' the cords to the base and the adjustable member respectively, and a common means for simultaneously ilexing said cords, said common meam comprising a pin oi' small diameter which may be moved longitudinally of the cords and about which' the cords are looped,'and a handle attached to said pin. y

4. A machine adapted izo-comparatively test the flexing durability oi' dissimilar tire cords comprising a base, means for maintaining the cords at the same elongation comprising an adjustable member mounted on the base, means for securing the mds of the cords to thebase and the adjustable member respectively, and a common means for simultaneously flexing said cords, said commonmeanscomprisingapin oismalldiameter about which the cords are looped, a handle attaches to ma pm 'and mams whereby mid pm a movable longitudinally ot the cords.

GERALD D. MALLORY. 

